With the popularity of application of the Internet, users have higher and higher requirements on network bandwidth, and how to implement a high-speed and secure access based on existing resources has become a focal point of research in the industry. The digital subscriber line (Digital Subscriber Line, DSL) network gains much attraction because it has a large number of users on a huge telephone network.
FIG. 1 shows a schematic diagram of a common reference architecture of a DSL network. T is a reference point between a user equipment (User Equipment, UE) and a residential gateway (Residential Gateway, RG) in a customer premises network (Customer Premises Network, CPN); U is a reference point between an RG and an access node (Access Node, AN), for example, a digital subscriber line access multiplexer (Subscriber Line Access Multiplexer, DSLAM). The CPN network and the access network are interconnected by using the DSL access technology. In an access network, an aggregation network exists between an access node and a broadband remote access server (Broadband Remote Access Server, BRAS) or a broadband network gateway (Broadband Network Gateway, BNG); V is an Ethernet aggregation reference point between the AN and the BRAS/BG in the access network; A10 is a reference point between the access network and the service provider (Service Provider, SP), where the reference point may connect an application service provider (Application Service Provider, ASP) to a network service provider (Network Service Provider, NSP) that provides the access network, or connects the NSP to a visited access network in a roaming scenario. In different types of networks, specific devices and technologies may be different. For example, in a passive optical network (Passive Optical Network, PON), the AN may be an optical line termination (Optical Line Termination, OLT) or an optical network unit (Optical Network Unit, ONU). The CPN and the access network are interconnected by using access technologies such as PON.
The existing DSL network is generally constructed based on Internet Protocol version 4 (Internet Protocol Version 4, IPv4). With the exhaust of the IPv4 addresses, it is a definite trend of evolving from IPv4 to IPv6. However, at present, the performance IPv6 is not perfect in many aspects. For example, a secure access, authentication, and authorization cannot be ensured. Moreover, the network cannot identify the type of a user equipment. Consequently, a same IPv6 prefix is allocated to different users, which affects normal routing. This has become one of the urgent problems to be solved in the industry.